diff options
Diffstat (limited to 'drivers/acpi/processor_throttling.c')
| -rw-r--r-- | drivers/acpi/processor_throttling.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index d6780f41d28c..18a873a55256 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -45,6 +45,14 @@ #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor_throttling"); +struct throttling_tstate { + unsigned int cpu; /* cpu nr */ + int target_state; /* target T-state */ +}; + +#define THROTTLING_PRECHANGE (1) +#define THROTTLING_POSTCHANGE (2) + static int acpi_processor_get_throttling(struct acpi_processor *pr); int acpi_processor_set_throttling(struct acpi_processor *pr, int state); @@ -196,6 +204,70 @@ void acpi_processor_throttling_init(void) return; } +static int acpi_processor_throttling_notifier(unsigned long event, void *data) +{ + struct throttling_tstate *p_tstate = data; + struct acpi_processor *pr; + unsigned int cpu ; + int target_state; + struct acpi_processor_limit *p_limit; + struct acpi_processor_throttling *p_throttling; + + cpu = p_tstate->cpu; + pr = processors[cpu]; + if (!pr) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n")); + return 0; + } + if (!pr->flags.throttling) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is " + "unsupported on CPU %d\n", cpu)); + return 0; + } + target_state = p_tstate->target_state; + p_throttling = &(pr->throttling); + switch (event) { + case THROTTLING_PRECHANGE: + /* + * Prechange event is used to choose one proper t-state, + * which meets the limits of thermal, user and _TPC. + */ + p_limit = &pr->limit; + if (p_limit->thermal.tx > target_state) + target_state = p_limit->thermal.tx; + if (p_limit->user.tx > target_state) + target_state = p_limit->user.tx; + if (pr->throttling_platform_limit > target_state) + target_state = pr->throttling_platform_limit; + if (target_state >= p_throttling->state_count) { + printk(KERN_WARNING + "Exceed the limit of T-state \n"); + target_state = p_throttling->state_count - 1; + } + p_tstate->target_state = target_state; + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:" + "target T-state of CPU %d is T%d\n", + cpu, target_state)); + break; + case THROTTLING_POSTCHANGE: + /* + * Postchange event is only used to update the + * T-state flag of acpi_processor_throttling. + */ + p_throttling->state = target_state; + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:" + "CPU %d is switched to T%d\n", + cpu, target_state)); + break; + default: + printk(KERN_WARNING + "Unsupported Throttling notifier event\n"); + break; + } + + return 0; +} + /* * _TPC - Throttling Present Capabilities */ |